Free, full Oregon CDL general knowledge test practice right here in your browser — real exam format (50 questions, 80% to pass), diagnostic and adaptive modes, spaced-repetition review, and a readiness dashboard. No signup, no paywall — your progress is saved automatically on this device.
If your front tires blow out, the vehicle will typically:
B. Pull toward the side with the blown tire — A front tire blowout causes the vehicle to pull toward the side of the blown tire. Grip the wheel firmly and steer to stay on the road.
What must you do before crossing a state line while transporting hazardous materials?
B. Verify that the HazMat regulations of the state you are entering allow the materials and routing — HazMat routing rules vary by state. Some materials require specific routes or are prohibited on certain roads within specific states. Before crossing state lines with HazMat, verify the destination state allows your specific cargo and chosen route.
What is 'outage' (or ullage) in a liquid tanker?
A. The space left empty in a tank to allow for liquid expansion — Outage (ullage) is the empty space left in a tank to allow the liquid to expand due to temperature changes. Different liquids require different outage amounts.
CDL safety scenario 58: What is the purpose of hours-of-service rules?
A. To reduce fatigue-related crashes — To reduce fatigue-related crashes. Commercial drivers are expected to manage this situation before it becomes a crash risk. The CDL manual emphasizes controlling the vehicle, inspecting safety-critical systems, and correcting hazards promptly.
Any CDL driver who discovers a hazardous materials leak should:
C. Keep people away, stay upwind, and avoid touching or inhaling it — Without proper training and equipment, keep clear, stay upwind, warn others, and call for trained responders to handle the leak.
During a pre-trip inspection, how do you check that the trailer's rear lights are working without a helper?
B. Use the cab controls to activate each light, then walk to the rear of the trailer to verify they are functioning, or use a reflective surface — Without a helper, activate each light (running, brakes, turn signal) from the cab, then walk to the trailer rear to verify operation. Alternatively, use a reflective surface (dock door, adjacent truck) to see the lights without walking.
When driving in heavy traffic, the most important thing is to:
C. Maintain a safe following distance and stay alert — In heavy traffic, maintain your following distance and stay fully alert. Avoid unnecessary lane changes.
What is the maximum number of passengers a transit bus may legally carry?
B. The seating capacity plus the number of standees up to the bus's rated capacity as marked on the bus — A bus may carry passengers up to its rated capacity, which includes both seated and standing passengers as allowed by the bus's certification. This capacity is typically marked on a placard inside the bus.
In a tractor-trailer combination, what does 'off-tracking' require you to do when making right turns?
A. Swing wide to the left before turning right so the trailer wheels clear the curb — Because the trailer wheels track inside the tractor path (off-tracking), drivers must swing wide (sometimes into the adjacent lane) before a right turn so the trailer tires do not ride over the curb or hit obstacles.
Shock absorbers should be checked for:
D. Leaks and secure mounting — Check shock absorbers for oil leaks, dents or damage, and loose or broken mounting hardware.
The Oregon CDL general knowledge test has 50 questions, and you need 80% to pass — at least 40 correct answers. The practice tests on this page use the same format. The 80% passing score is a federal FMCSA standard used by every state.
80%. You can miss at most 10 of the 50 questions. The readiness dashboard on this page tracks whether you're consistently scoring above that bar.
Yes. Every practice test on this page and everything in the DMVPrep iPhone app is free — no ads, no paywall, no account.
Federal motor carrier safety regulations (FMCSA) — the same rules every state's CDL exam is drawn from. Every question in the DMVPrep app cites the regulation or handbook section it comes from.
Yes — the DMVPrep app includes all 3,745+ questions in Spanish, and the whole app works in Spanish.